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231.
An adaptation procedure of a new emission inventory of theGreater Athens Area is attempted, based on a sensitivityanalysis on the treatment of the VOC emissions. Throughthis procedure the impact that a more detailed treatment ofthe VOCs emissions might have on the atmospheric chemistrysimulations, is examined. For this analysis three differentchemical mechanisms were applied for two differentlocations (urban and city plume) with different VOC andNOx mixture characteristics. Finally, this studyrecommends new carbon fractions, reflecting the localconditions in Athens basin.  相似文献   
232.
CWAO催化剂及其在废水处理中的应用   总被引:2,自引:0,他引:2  
催化湿式氧化技术是在高温高压条件下处理高浓度、有毒有害且难生物降解污染物的一种高级氧化技术。本文在检索了国内外大量参考文献的基础上,概述了催化湿式氧化技术的最新进展、机理及动力学,总结了催化湿式氧化技术中催化剂的分类、组成、特点及其在废水处理中的应用,以期对有关研究者提供一定的借鉴作用。本文最后肯定并展望了催化湿式氧化技术是有广阔应用前景的水处理技术。  相似文献   
233.
环境标志对珠江三角洲经济发展的影响,展望及对策   总被引:2,自引:0,他引:2  
论述了环境标志的产生及发展,并通过其对珠江三角洲经济发展的影响分析,提出了珠江三角洲实施环境标志,发展环境标志产品的展望及对策。  相似文献   
234.
铝盐混凝去除氟离子的作用机理探讨   总被引:28,自引:1,他引:28  
在烧杯搅拌实验的基础上,通过絮体的ζ电位测定、X射线粉晶衍射、红外光谱、X射线光电子能谱等实验手段考察了铝盐混凝除氟的作用机理。结果表明,铝盐混除氟的主要作用机理有吸附、离子交换、络合沉降等。对于两种形态的铝盐,从除氟过程和机理上看,单体铝盐中的Al(H2O)6^3 形态要比聚合多中的聚羟铝阳离子形态更有利,因而总体除氟效果和比聚合铝要好。  相似文献   
235.
钠钙双碱法烟气脱硫主要影响因素的实验研究   总被引:8,自引:0,他引:8  
采用纤维栅洗涤器在实验室对钠钙双碱法烟气脱硫效率的主要影响因素 :洗涤器的风速、烟气SO2 初始浓度、吸收液 p H值及 [Na+ ]浓度、液气比等进行了模拟实验 ,得出了它们与烟气脱硫效率的关系。  相似文献   
236.
One of the basic principles of sexual selection is that male reproductive success should be skewed towards strong males in species with anisogamous sex. Studies on primate multi-male groups, however, suggest that other factors than male fighting ability might also affect male reproductive success. The proximate mechanisms leading to paternity in multi-male primate groups still remain largely unknown since in most primate studies mating rather than reproductive success is measured. Furthermore, little research focuses on a female’s fertile phase. The aim of this study was to investigate the relative importance of male monopolisation and female direct mate choice for paternity determination. We also investigated the extent to which paternity was decided post-copulatory, i.e. within the female reproductive tract. We used a combined approach of behavioural observations with faecal hormone and genetic analysis for assessment of female cycle stage and paternity, respectively. The study was carried out on a group of wild long-tailed macaques living around the Ketambe Research Station, Gunung Leuser National Park, Indonesia. Our results suggest that both male monopolisation and post-copulatory mechanisms are the main determinants of male reproductive success, whereas female direct mate choice and alternative male reproductive strategies appear to be of little importance in this respect. Female cooperation may, however, have facilitated male monopolisation. Since paternity was restricted to alpha and beta males even when females mated with several males during the fertile phase, it seems that not only male monopolisation but also post-copulatory mechanisms may operate in favour of high-ranking males in long-tailed macaques, thus reinforcing the reproductive skew in this species.  相似文献   
237.
侯喜福 《干旱环境监测》1992,6(2):114-115,121
就当前建设项目对大气环境影响的环境质量评价中存在的问题,进行了论述,指出五个较突出的问题,以求改进,保证评价报告书的质量.  相似文献   
238.
Objectives: The aim of this article is to report on the possible relationships between tramway front-end geometry and pedestrian injury risk over a wide range of possible tramway shapes.

Methods: To study the effect of tramway front-end shape on pedestrian injury metrics, accidents were simulated using a custom parameterized model of tramway front-end and pedestrian models available with the MADYMO multibody solver. The approach was automated, allowing the systematic exploration of tramway shapes in conjunction with 4 pedestrian sizes (e.g., 50th percentile male or M50).

Results: A total of 8,840 simulations were run, showing that the injury risk is more important for the head than for other body regions (thorax and lower extremities). The head of the M50 impacted the windshield of the tramway in most of the configurations. Two antagonist mechanisms affecting impact velocity of the head and corresponding head injury criterion (HIC) values were observed. The first is a trunk rotation resulting from an engagement of the lower body that can contribute to an increase in head velocity in the direction of the tram. The second is the loading of the shoulder, which can accelerate the upper trunk and head away from the windshield, resulting in lower impact velocities. Groups of design were defined based on 2 main parameters (windshield height and offset), some of which seem more beneficial than others for tramway design. The pedestrian size and tramway velocity (30 vs. 20?km/h) also affected the results.

Conclusions: When considering only the front-end shape, the best strategy to limit the risk of head injury due to contact with the stiff windshield seems to be to promote the mechanism involving shoulder loading. Because body regions engaged vary with the pedestrian size, none of the groups of designs performed equally well for all pedestrian sizes. The best compromise is achieved with a combination of a large windscreen offset and a high windscreen. Conversely, particularly unfavorable configurations are observed for low windshield heights, especially with a large offset. Beyond the front-end shape, considering the stiffness of the current windshields and the high injury risks predicted for 30?km/h, the stiffness of the windshield should be considered in the future for further gains in pedestrian safety.  相似文献   
239.
The natural histories of crop-related wild species in their native habitats can be used to develop novel pest management strategies. Traditionally, such information has provided insights for biological control, plant breeding, crop management, and applied ecology Further insights can be garnered.  相似文献   
240.
Condensed atmospheric photooxidation mechanisms for isoprene   总被引:1,自引:0,他引:1  
Two condensed mechanisms for the atmospheric reactions of isoprene, which differ in the number of species used to represent isoprene's reactive products, have been developed for use in ambient air quality modehng. They are based on a detailed isoprene mechanism that has recently been developed and extensively evaluated against environmental chamber data. The new condensed mechanisms give very close predictions to those of the detailed mechanism for ozone, OH radicals, nitric acid, H2O2, formaldehyde, total PANS, and for incremental effects of isoprene on ozone formation in one day simulations. The effects of the condensations become somewhat greater in multi-day simulations, particularly in cases where NO3 reactions are important at nighttime, but the ozone predictions are still very close. On the other hand, the SAPRC-90, RADM-2, and Carbon Bond IV isoprene mechanisms give quite different predictions of these quantities. It is recommended that the new mechanisms replace those currently used in airshed simulations where isoprene emissions are important.  相似文献   
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